The invention relates to a shower gel formulation.
Shower gel formulations which are mild to the skin are well known in the art. Such a formulation may optionally contain skin feel agents, such as cationic polymers. However, when one design is to suspend particulates and/or beads in the formulation, frequently substantial quantities of anionic surfactants have been incorporated and provide clear solutions. Unfortunately, the addition of such anionic surfactants diminishes the mildness of the shower gel formulation. U.S. Pat. No. 5,656,257 (Fealy et al., issued on Aug. 12, 1997), which is here incorporated by reference, discloses an anionic shampoo and conditioning composition comprising an oily conditioning agent, a shampooing agent, and an acrylate copolymer, a cationic conditioning agent and water. In this formulation, the acrylate copolymer is used to suspend the anionic shampooing and cationic conditioning agent and prevent it then from inactivating one another. U.S. Pat. No. 5,656,257 does not, however, disclose a clear, mild cleansing composition containing a combination of surfactant types, which is capable of suspending beads or other insoluble particulates or gas bubbles. U.S. Pat. No. 4,552,685 (Kernstock et al., issued Nov. 12, 1985), which is here incorporated by reference, discloses examples of useful acrylate polymers and copolymers capable of thickening mild cleansing agents containing amphoteric surfactants and betaines. However, there is no disclosure regarding the compatability of cationic polymer conditioning agents in the formulation nor the suspending power of the solution for insoluble beads, particulates or gaseous bubbles.
U.S. Pat. No. 3,759,861 (Shimokawa, issued Sep. 18, 1973), which is here incorporated by reference, discloses a clear polymer adhesive complex of an acrylate containing polymer and surfactant used to produce a flocculant. However, there is no disclosure of a shower gel or other cleansing composition containing a cationic conditioning agent or complex which can suspend particulates or gas bubbles.
The present invention comprises a shower gel formulation having a clear appearance and which suspends beads (e.g. agar/TiO2/sunflower oil beads) insoluble particles and gas bubbles while having one or more acrylate copolymers, a betaine, or other amphoteric surfactant and a cationic polymer (e.g. guar) present in the formulation. It is known that anionic acrylates (i.e. Aculyn type acrylates (available from ISP)) being anionic polymers are generally considered to be incompatible with cationic charged ingredients. It is further known that polymeric cationics, as well as some large, bulky quaternary materials, can possibly be incorporated in formulations containing such acrylates. The optimum order of addition in these instances generally requires the acrylate to be neutralized with a base prior to the addition of any cationics. Applicants have discovered that a clear or transparent product can be produced by either partially neutralizing such acrylates prior to cationic addition or after cationic addition. Clarity or transparency is herein defined as having a turbidity less than or equal to 105 NTU (Nephelometric Turbidity Units).
Applicants have further discovered that amphoteric surfactants, such as Betaine (which is also cationic in nature and not a true amphoteric), may be optionally added to the inventive formulation in the range of 0.01-15 weight percent, preferably 1-10 weight percent to increase mildness without creating noticeable haziness. Prior art shower gels that suspend beads or particulate matter are primarily composed of anionic surfactant and structurant which in most cases are harsher than the inventive formula.